2013年4月20日8时2分在四川省雅安市芦山县发生的7.0级地震,是继"5.12"汶川地震之后相隔约5年发生的又一次强震。作者在收集了遥感、DEM、地面地质及芦山震区人工地震剖面基础上,对网上公布的芦山地震震中数据、地震机制解、余震分布数据和地震的地表破裂情况进行了分析,初步推断引发芦山地震的断裂是盆地内西南侧地腹隐伏断裂或新生断裂。将芦山地震与汶川地震进行了综合对比,认为2次地震均属构造地震,从构造动力学角度分析均与印度板块向北挤压碰撞有关;但2次地震发震断裂和发震构造单元特征是不同的,应属2次独立地震。
The 7.0 magnitude earthquake occurred in Lushan County (epicenter: 30.3 degrees north latitude and 103.0 degrees east longitude) of Ya'an City in Sichuan at 8:02 a. m. on April 20, 2013. It is another destructive earthquake after the "5 . 12" Wenchuan earthquake. On the basis of data on remote sensing, DEM, surface geology and the seismic profiles of the Lushan quake-struck zone, the paper analyzes the epicenter data, earthquake mechanism, the aftershocks distribution data and surface rupture published online. This paper concludes preliminary that the earthquake-triggering fracture of the Lushan earthquake should be the ventral buried fault or the new fracture in the southwest within the basin. And the comprehensive comparison between the Lushan earthquake and the Wenchuan earthquake shows that both of them are tectonic earthquakes. As viewed from tectonic dynamics, the authors consider that the two earthquakes are relevant to the northward extrusion and collision of the Indian Ocean Plate. However, there are differences between them about their earthquake-triggering fractures and the characteristics of the earthquake-triggering tectonic unit. Above all, the authors conclude that they should be two independent earthquakes.